From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4A611F03FF for ; Tue, 25 Mar 2025 19:22:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742930529; cv=none; b=OkJzZR4fkWVZxVdVy6Kvwrc42NDexwrL6HtthJI2sl1jqNB2NoATrm1lbauEtUoAnKH1CWvYYXn/8Vl2iALYE6GpVxY0VIQsQBC0K+c4RCSQ30U7O0r0YHBGpmkaW8fFCsWD+Uv8A/Sncz1ecsUI6Wagmn3nm3BL6iKih371u84= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742930529; c=relaxed/simple; bh=LN+/bd2Olj3N0EdJKGdRLMdju9OGCP1EWi9G0sWNNZI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qImDO1i6YGdRbUwCMkaIOco2ZwexlC+zr4+ZgN+U5c6wtZnSUp72gBlTGQqoBTeNAVTYp38B641QYD1QqTtNxjgybomXwySBsilyuXQEtG7Am7OJagHFE7AgaUjrEt6zwMb4h0Q4MW3i69v/ICukDu/20ubt/W+9Sb4f2WAq1ig= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=AJpo43Bz; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AJpo43Bz" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1742930526; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=4uusw5Mfq776t99OEEpC16y3um4OcX5n1LocwgSdxeo=; b=AJpo43BzFOMWGAQ1ZRUVCUqCcPbHmPbPxJZjHeSipor7T8azpXYu3jm6v8g/QpIsB5ZbyF 56jUgcDlx8VCwHOrpUYfaIlfGZ1/LjaB/5vzNrsdK4QKNBJciB+nRZHO2Sq8QM8/i2z2gf +zw5Xq5VmmLZLJFvy2sUtKw+Oq4LK1E= Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-629-AztWwTZZPIKuyfsfAnYWMg-1; Tue, 25 Mar 2025 15:22:05 -0400 X-MC-Unique: AztWwTZZPIKuyfsfAnYWMg-1 X-Mimecast-MFC-AGG-ID: AztWwTZZPIKuyfsfAnYWMg_1742930525 Received: by mail-qk1-f198.google.com with SMTP id af79cd13be357-7c5d9d8890fso26675885a.1 for ; Tue, 25 Mar 2025 12:22:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742930524; x=1743535324; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=4uusw5Mfq776t99OEEpC16y3um4OcX5n1LocwgSdxeo=; b=owRWprkZ3/OaSgwM7UdBOZE62OETlmxhjbBRb4VoQgtnc/NzdjfqBk3zPRW2GOQzkp 0Wz7+MZSP4uUnggWBLXifgHrCuDFZMDwRHxQ1llw7WqNeQ6/TJEapGM27Tn+rX72lQEZ wrFSfJiAZD+tch7sB+oCA2D0pB41ffEIn9bKMIv8Aq6LNF0pq5UTt1euC7euGRrBfbyS egIQUWi5JnGEujSKbL2ALrRrCx4DZrYAr5wXMnkLntnZ13vtFqkbhlWvATUZF5d1nW5V pBqVMvtDS7/L1q0UGjnpWxfHzHPEXwTYZVfZaoJ+vMas12TcVBXwDMdEOP/3mN496UQs xl9A== X-Forwarded-Encrypted: i=1; AJvYcCWSC1y5S2iMklBgbQ8n/maRworcrK8kc28FVCL+9C2hVlaeEQQfdyUEScxXltnE1a90LtZ9Nqg6LdBSmgI=@vger.kernel.org X-Gm-Message-State: AOJu0Yw/NUJBXuGBEnkm2UvcJWfBbayvLw7WIjCSah7aSwvPAUm+J1Qt WkxtMx/0ORzjv3Nh6/3kuwMGID2np8noLWr8Jru6hN9AOnJdu5YYZRPL8eaJz4MAPl99RLO9tMf dlYNjapu8rQsfZY7ndbTYtjKM/s3g7T8dUqjjBdGcaeqEt9aV+U9XYYiv0m6+JQ== X-Gm-Gg: ASbGncv1Wtfxc6ISL0ugsg7PxGuVXN2rlBcOY7nG0EWqR94gV2gwOMKC4g6A4Hj9WUK 1otZBCb0Z5GYJN4JDyGnV5hlnyvpEg+8iapimJTlx8EKlUSYefceFoxCrLLcSfRbo/t8HnWdyg6 Vl2IrP7tgD/9zjbrC0v4ALUNTBjIgTGly6Nco7S5VaY9PtsyMWqxl+9BDVfinXdLrUMzwrfelIi P/qIdRJKY9ckOAKLKFYhQYTQXJ0CvPWOK6sN96H6mx+IlORy83GiekpiptUrVk2FwCyu0dMCzk9 a9DieDbSx3+3 X-Received: by 2002:a05:620a:1d03:b0:7c0:a264:4de1 with SMTP id af79cd13be357-7c5e494b431mr151018085a.24.1742930524602; Tue, 25 Mar 2025 12:22:04 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGEXSfDMRz0JKf36Wpss30g3vtLjnFK8ezZQX4sG9FZ6Z+Fvfb2FbRMSHP6VydBgJHZ4ZfB+g== X-Received: by 2002:a05:620a:1d03:b0:7c0:a264:4de1 with SMTP id af79cd13be357-7c5e494b431mr151015185a.24.1742930524235; Tue, 25 Mar 2025 12:22:04 -0700 (PDT) Received: from [172.20.3.205] ([99.209.85.25]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7c5b92ec63dsm668951985a.62.2025.03.25.12.22.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 25 Mar 2025 12:22:03 -0700 (PDT) Message-ID: <1767a68b-cb2e-425c-86bb-bc8e5289ee99@redhat.com> Date: Tue, 25 Mar 2025 20:22:02 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] arm64: mm: Correct the update of max_pfn To: Zhenhua Huang , anshuman.khandual@arm.com, catalin.marinas@arm.com, will@kernel.org, ryan.roberts@arm.com, mark.rutland@arm.com, ardb@kernel.org, yangyicong@hisilicon.com, joey.gouly@arm.com, quic_cgoldswo@quicinc.com, quic_sudaraja@quicinc.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, quic_tingweiz@quicinc.com References: <20250321070019.1271859-1-quic_zhenhuah@quicinc.com> From: David Hildenbrand Content-Language: en-US Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <20250321070019.1271859-1-quic_zhenhuah@quicinc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 21.03.25 08:00, Zhenhua Huang wrote: > Hotplugged memory can be smaller than the original memory. For example, > on my target: > > root@genericarmv8:~# cat /sys/kernel/debug/memblock/memory > 0: 0x0000000064005000..0x0000000064023fff 0 NOMAP > 1: 0x0000000064400000..0x00000000647fffff 0 NOMAP > 2: 0x0000000068000000..0x000000006fffffff 0 DRV_MNG > 3: 0x0000000088800000..0x0000000094ffefff 0 NONE > 4: 0x0000000094fff000..0x0000000094ffffff 0 NOMAP > max_pfn will affect read_page_owner. Therefore, it should first compare and > then select the larger value for max_pfn. > > Fixes: 8fac67ca236b ("arm64: mm: update max_pfn after memory hotplug") > Signed-off-by: Zhenhua Huang > --- > arch/arm64/mm/mmu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index 1dfe1a8efdbe..310ff75891ef 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -1361,7 +1361,8 @@ int arch_add_memory(int nid, u64 start, u64 size, > __remove_pgd_mapping(swapper_pg_dir, > __phys_to_virt(start), size); > else { > - max_pfn = PFN_UP(start + size); > + /* Address of hotplugged memory can be smaller */ > + max_pfn = max(max_pfn, PFN_UP(start + size)); > max_low_pfn = max_pfn; > } > Yes, that's the right thing to do. (I always wonder if these values should be atomically updated ...) Acked-by: David Hildenbrand -- Cheers, David / dhildenb